A vocoder with smooth integration in Studio One would be awesome!! I could take or leave an FM synth though, unless it had some interesting new features vs. FM8 or Dexed.
I do understand the point chancekaye made regarding priorities but having an easy-to-use, flexbile, and built-in vocoder could save a lot of time and it really helps the flexbility for vocoders to have good integration with the host DAW.